The invention discloses a multifunctional aqueous nano-coating. The multifunctional aqueous nano-coating comprises the following components in parts by weight: 20-40 parts of water, modified cellulose ether, 2-amino-2-methyl-1-propanol, a dispersing agent, a polyether type surfactant, polydimethylsiloxane, polyoxyethylene polyoxypropylene glyceryl ether, a CMIT-MIT compound, 2,2,4-trimethyl pentanediol-1,3-monoisobutyrate, an anti-freezing agent, rutile type titanium dioxide, 25-50 parts of fillers, 0.2-1 part of nano-silver powder, polyorganosiloxane, 1-2 parts of fluoro-alkyl-polyether modified silicone, nano-titania aqueous colloid, an emulsion and a mildew preventive, wherein the main components of the CMIT-MIT compound are 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one. The multifunctional aqueous nano-coating has the efficacies of sterilization, formaldehyde purification and negative ion release; no harmful chemical substance is added in the whole process, and testing proves that the sterilization efficiency can reach above 99% within 24 hours, and the formaldehyde purification efficiency can reach above 80%.